If he just comes to buy something and leaves, I won't have a problem. I'll simple provide him what he ASKS for. 

Such customers are very difficult to handle as they do not have ability to understand at that point of time. They NEED to be handled in a friendly manner rather than being RUDE to them. I would try to fulfill his requirement and politely MAKE him leave. The problem arises when a drunk customer creates a scene.

If he misbehaves with any customer or employee and is not ready to LISTEN, I might need to call the security or police.

If he just comes to buy something and leaves, I won't have a problem. I'll simple provide him what he asks for. 

Such customers are very difficult to handle as they do not have ability to understand at that point of time. They need to be handled in a friendly manner rather than being rude to them. I would try to fulfill his requirement and politely make him leave. The problem arises when a drunk customer creates a scene.

If he misbehaves with any customer or employee and is not ready to listen, I might need to call the security or police.